Mercury dispenser



Dec. 15, 1953 H. E. BAKER 2,562,678

' MERCURY DISPENSER Filed March '7, 1951 2 Sheets-Sheet l INVENTOR HAROLD E. BAKER MEW C ATTOR Y Dec. 1-5, 1953 H. E. BAKER 2,662,678

MERCURY DISPENSER Filed March 7, 1951 2 Sheets-Sheet 2 INVENTOR HAROLD E. BAKER ATTO EY Patented Dec. 15, 1953 MERCURY DISPENSER Harold. E. Baker, Danvers, Mass,., a ssignor to. Sylvania, Electric Broducts I'nc.,. Salem, Mass. a. corporation of Massachusetts,

Application; Marchth, 1951, Serial No. 214,380

lrclaim.

This. invention relates; to thermanufacture; of,

electric gaseousv dischargedevices: and more par.-

ticularly to apparatus for introducing mercuryinto said devices during the manufacture thereof. In the art of manufacturing certain, electric gaseous discharge devices, such as, fluorescent: lampsior-example, a small amount of mercuryv is introduced, into; the; devices; during the menu:

facture thereof, In. many cases, the: quantity, of mercury, to. be introduced, is a definite,- p-redetev mined amount and. any. Substantial deviation therefrom adversely. aiiects the; device.

An object or". thisinventionis-to, provide elecr,

tricgaseous-discharge, devices witha filling; of.

a definite, predetermined quantityof mercury.

Another object isrto provide an: apparatus which will. dispense a; definite predetermined amount.

of mercury.

A further, object ,is, toprovide awmercury, dispenser, which. is positive, in; its action; and dispenses a uniform predeterminedamount.of, mer-.

cury each time it i actuated The foregoing objects and -othersare attained, in accordance; with, the principles of this inven.-

tion, by providing a-reservoir with a,. p1un r disposed therein which, when, actuated, shears a; predeterminedamount. of mercury. from asupply, thereof in .the r,eser voir, and drops it directly into. the device which. is l to. be, provided, with a, filling of mercury.

A specific embodiment of this invention is described in the following specification and illustrated, in the, accompanying; drawings iniwhichz Figure 1 15a fragmentary plan view of a fluorescent lamp exhaust machine showing the location of an embodiment of the invention thereon.

Figure 2 is a fragmentary-side elevationalview of the machine of; Figure 1.

Figure 3 is an enlarged side, elevational view in section, taken along line 3+3, of. a station .on the machine of- Figure 1", showing the mercury dispenser of this invention. In this figure, the plunger of the mercury dispenser is shown in its normal rest position.

Figure 4 is a plan view in section of the mercury dispenser taken along the line 4-4 of Figure 3 In Figure 1, that portion of a fluorescent lamp exhaust machine shown therein comprises a rotatable turret I supported on a vertical column 2. The turret I comprises a hub 3, a plurality of supporting arms 6 extending radially therefrom, and a ring plate 5 mounted on the outer ends of the arms 4. In Figure 2, a plurality of lamp exhaust heads 6 are mounted on the top face of the. ring; plate; 5;, Fluor scent. l mps. it hav ng:

exhaust tuloesv 8 proiectingirom an end: thereofv are disposed: beneath: thexheads 6 andin. regis-. ter therewith, the exhaust; tubes; 8;; extending;

through apertures. provided; therefor in; theyring plate-Band into theexhaustheads; 6;. The; ex? haust hea sa r re connectedtea-vacuum system. which; is; notshown. since, theillustration;thereof,-

is. notnecessary for; a; complete;understandin of. thi invention. The, fluorescent; lamps; t are: held in position -by .-fingers;5;on rods iflwdepending,

from the I ring plate: 51.,

Each exhausthfiad 61 has; a; mercury, dispens r- H mountedon; the,- top; thereof; Actuation. of: the mercurvwdispensers l t isfiectedby eiectroe agnets, I12, two, of; which are; shown; in; Figures-i. Thaelectromagnets: l2: are connected;

1 to a source of; elcctricalaener (noirshown); by; means-,ofj'wires;lfiiextending:,thereir om; Aepir r;

Wis fixedly; monntedon'the column-Zandis;dis-- posed; a-bovetherturret; L Anarnrl5 istmountfidv on the spider M and extendstr diallv:therefromi.

The electromaenets I are;- mounted. on; plat I a; attachedto the outer end; ofithe; arnr 551.;

nFisurehe mercury: disp nser H whichis: mounted on; the exhaust; head; 8 has; two; main; components,. a jacket; l-lrarid aaplunger; [8. dis:- po sed;the11ein;, The: jacket; H hasa; reservoirs I31:- her in r; an pplyr of; mercury... 20;; The; jacket. ilahasnar; base-2L which is sorrewrediinto;the;top* of; the exhaust headtl. The exhaust'head' is; bored o provide afunnel;2 2 therein;immediately. below-and ,inregisterzwith themounting position.

of the jacket Ii. Thisrfunnelt 2sisr'ingeommurnication, with; the; exhaust tube; Blot? the, lamp; T2; The baseZlof the; jacket; It is bored: through. from the; end thereof to the; floor,- 23; of; the reservoir; Iii-i. The holen o -med thercby simada larger-in diameter: at the 'endiof the; base; 2;! and,

h s; pening. s; dentified: by reference numera-r whe easgthe smaller op inexinz OIH UBiQQLr tion with the reservoir 59 is identified by reference numeral 25.

The plunger I8, which is disposed in the jacket [1, has a head 26 normally located above the surface of the mercury supply 20 and a shank 21. The shank 21 extends downwardly through the openings 24 and 25 in the base 2| of the jacket IT. The lower portion 29 of the shank 21, which is disposed in the openings 24 and 2-5 in the base 2|, is smaller in diameter than the upper portion 21, the point of demarcation between-the two diameters defining a shoulder 28 which seats on the floor 23 of the reservoir [9 when the plunger is in the rest position. The

lower portion 29 of the shank 21 has a recess preferably a notch 3|, cut in its periphery. The plunger I8 is preferably tubular having a hole 32 bored completely through it along its longitudinal axis, and the head 2| thereof preferably has cut-outs 33 (Fig. 4) in its periphery to prevent any pressure being built up in the mercury reservoir due to the operation of the plunger H3.

The top of the jacket I! is provided with a shelf 34 on which a ring 35 of resilient material, preferably circular in cross-section, is located. A pressure plate 36 is positioned on top of the ring 35. The top of the jacket I1 is closed by a threaded cap 31 which, when turned down handtight, engages the top of the pressure plate 36 and thereby effectively seals off the mercury supply 20 from the atmosphere.

The jacket H, the pressure plate 36 and the cap 31 are all made of a non-magnetic metal which is not attacked by contact with mercury, such as non-magnetic stainless steel, whereas the plunger I8 is made of magnetic metal which is not attacked by contact with mercury, such as magnetic stainless steel.

The operation of the mercury dispenser of this invention will now be described. As mentioned above, a mercury dispenser is mounted on each head 6 of a rotatable turret type lamp exhaust machine which carries the heads 5 to a plurality of work stations at which various operations are performed on the lamps l which are connected to the heads. One of these operations is the introduction of mercury into the lamps, which is performed at the mercury-filling station. The particular machine with reference to which the mercury dispenser of this invention is illustrated. is provided with two mercury-filling stations in order to permit two lamps to have mercury introduced therein at the same time. When this is accomplished the machine indexes and two more lamps are brought into position to have mercury dispensed thereto.

Referring now to Figures 1 and 2, when a pair of heads 6 reach the mercury-filling position beneath the electromagnets I2, the electromagnets are energized. Referring now to Figure 3, energization of the electromagnet l2 draws the plunger l8 upwardly until the notch 3| in the perphery of the lower portion 29 of the shank 21 thereof is disposed above the floor 23 of the reservoir I9. When the plunger |8 is so located, some of the mercury will flow into and fill the notch 3|. The electromagnet I2 is then de-energized, thus permitting the plunger l8 to drop back to its starting position with the shoulder 28 on the shank 21 of the plunger seating on the floor 23 of the reservoir [9. As the plunger drops and the notch 3| moves down into the opening 25 in the base 2| of the jacket H, the mercury which had previously entered the notch is sheared from the main supply 20 thereof by the wall of the opening 25. This drop of mercury, the quantity of which is accurately predetermined by the size of the notch, is retained in the notch 3| until the plunger drops down far enough for the notch 3| to be located in the opening 24. Since the opening 24 in the base 2| of the jacket H is substantially larger in diameter than the diameter of the lower portion 29 of the shank 2'! of the plunger IS, the drop of mercury in the notch 3| will fall out and drop through the funnel 22 in the head 6 and into the lamp 1 through the lamp exhaust tube 3. Any tendency which this drop of mercury may have to stick in the notch 3| after the notch enters the opening 24 in the base 2| of the jacket I! is obviated by the shock of the shoulder 28 on the shank 21 of the plunger I8 seating on the floor 23 of the reservoir What I claim is:

Apparatus for dispensing measured amounts of mercury comprising: a rotatable turret moveable to a plurality of work stations; a reservoir fixedly mounted on said turret, said reservoir being of non-magnetic metal, having a body of mercury therein and an opening in the bottom thereof; a plunger of magnetic metal having a head and a shank disposed completely within said reservoir, said head being disposed immediately above the surface of the body of mercury, and said shank extending through the opening in the bottom of said reservoir and in sliding contact with the wall of the upper portion of said opening, said plunger having a recess cut in the periphery of its shank and normally disposed below that portion of the opening in the bottom of the reservoir with which the shank is in sliding contact; a cap of non-magnetic metal closing the top of said reservoir, and an electromagnet fixedly mounted above and in register with one of said work stations and disposed above, in close proximity, and, at all times, maintaining the same vertical spacing between itself and the cap of the reservoir for permitting unobstructed movement of said reservoir to a position beneath the electromagnet and in which position the electromagnet, without moving, is effective to reciprocate said plunger to carry the recess in the shank thereof into contact with the body of mercury in said reservoir and return with a drop of mercury therein.

HAROLD E. BAKER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,374,304 Owings Apr. 24, 1945 FOREIGN PATENTS Number Country Date 581,656 Great Britain Oct. 21, 1946 

